ADMINISTRATIV E RECORD

UNITE D STATE S ENVIRONMENTA L PROTECTIO N AGENC Y

REGIO N VII I

IN TH E MATTE R OF :

CALIFORNI A GULC H SUPERFUN D SITE , ASARC O INCORPORATED ,

RESPONDENT .

PROCEEDIN G UNDE R SECTIO N 106(a ) OF TH E COMPREHENSIV E

ENVIRONMENTA L RESPONSE , COMPENSATION , AN D LIABILIT Y ACT , AS AMENDED , 42 U.S.C . § 9606(a )

348194

S&? FILEPLA N

" TJ

Secon d Order EPA Docket NOT CERCLA-VIII-91- 1 9 ~

SECOND AMENDMENT TO ADMINISTRATIVE ORDER FOR CERTAIN REMEDIA L INVESTIGATION STUDIE S

As provided under Paragraph 84, Sectio n XXVIII, page 20, of

t he above referenced Administrative Order, the Order is hereby

amended as follows :

1. Paragraph 12 is amended to read as follows : Afte r the

firs t sentence add "Work Plan" also means the "Smelter Site Investigatio n Work Plan , California Gulch Site , Leadville , Colorado, August 1991," affixed to the Second Amendment to this Order and hereafter to be referred to as Exhibit 8 to this Order.

2. Appendix A to the above referenced Order is amended by

adding the followin g new section:

F. Changes to Smelter Site Investigatio n Work Plan , California Gulch Site , Leadville, Colorado, August 1991, Exhibit 8.

1) Section 2.3.3, Page 2-8: At page 2-8 afte r the

subsection entitled "Reporting," the followin g

subsections are added as clarificatio n of the

modeling effort :

Meteorological Data

Meteorological data collected from a weather station located at

Colorado Mountain College in Leadville will be used for modeling. Thi s station has collected hourly averages of wind speed, wind

direction, temperature, relative humidity, and wind stabilit y

(expressed as sigma theta ) since installatio n in October, 1990.
T he period from October 1, 1990 through September 30, 1991 was

used for modeling. Since the use of data from one meteorological

station is insufficient , a review will be conducted of several

years of meteorological data collected at the Leadville airport

to determine if the period selected is anomalous.

Model Input Parameters For Each Smelter Location (DERIVED FROM LITERATURE )

The parameters needed as input to the model for each smelter

included the following:

o Location and elevation;

o Dates of operation (emissions start and end dates,

length of operation);

o Type s and numbers of stacks;

o Stack heights and inner diameters;

o Exhaust temperatures and velocities;

o Metal concentration in exhaust (related to production

rate) ;

o and, Particle size distributions for smelter emissions.

Attempt s were made to obtain actual data specifi c to each smelter

for each parameter of interest. However, when actual data were

unavailable, alternative approaches, (i.e. , comparisons to

similar operations) were used in order to arrive at reasonable

estimates of the values.

Particle size distribution data for roasters and blast furnaces

were estimated based on information provided by ASARCO. Table 1 (Attachmen t 1 ) list s the estimated particle size distributions

f or controlled and uncontrolled roasters and blast furnaces for

use in air dispersion modeling. The particle size data were

based on measured size distributions from similar smelter

operations at East Helena, Montana. Due to the lack of specifi c

informatio n concerning historical smelter operations in the Leadville area, the particle size distributions for both the

roaster and blast furnace are assumed to be representative of

both controlled and uncontrolled emissions.

T he Input Parameter Table (Attachment 2) list s the values for the

input parameters. Columns 1 through 25 are values taken from

historical data or estimated based on available information . Columns 26 through 39 contain values from columns 1 through 25

which have been converted, using simple mathematical

calculations , ratios, and proportions, into units for modeling

purposes.

T he followin g are brief description s of the informatio n contained

in each column of data, firs t to the left , and then to the right

of the vertical dividin g line on the Input Parameter Table . Each
column is identified and discussed, reading the table columns in

order.

Column 1. Smelter No.

i

T he smelters were sequentially numbered for reference

purposes.

Column 2. Emission Point

Locations of smelters, labeled on the table as emission

point , were determined from historic maps or existing

reports, and/or field-located. The locations were then

mapped on a CAD system, and the coordinates were

derived from the mapping. All smelters were either

field located and/or foun d on historic maps, except for

t he California Smelter. It was cited, for modeling

purposes, south of the Arkansas Valle y (AV) Smelter,

where historic data indicates the smelter existed prior

to being destroyed.

Columns 3 and 4. Easting State Coordinate and Northin g State Coordinate

T he coordinates listed in these columns are State Planar Coordinates. They represent the approximate

central point of each facility . All emissions for a

given facilit y wil l be modeled as originating from the

point identified by these coordinates.

Column 5. Elevation (ft )

Elevation for each point was derived from the mappin g

described previously.

Columns 6 and 7. Emissions Start Date (Year) , Emissions End Date (Year )

Historic documents and recent reports provided detail s

concerning the dates of operation at each smelter, as

well as the changes in facilit y operations over time

(e.g. , number and types of furnaces , and dust control

technologies). These data will be used to model the

exhaust contributions of individual stacks (or groups

of similar stacks at the same site during the same time

period ) and to include exhaust from dust stacks as well

as furnace stacks, when such data are available.

Column 8. Length of Operation (days )

The dates of operation, described above, were used to
estimate the total number of days (ofte n over several

years) each stack or group of stacks operated.

Column 9. Stack Type* (B,BD,D,RD )

Stacks are categorized according to function s as

follows: j

B = Blast furnace stack (without dust controls ) BD =Blast furnace stack with associated dust stack 

D = Dust stack from dust chamber or baghouse 

associated with a blast furnace RD = Dust stack associated with a reverbatory (i.e.,

roasting) furnace ;

A review of historical data indicates that only two

types of furnaces were commonly used, namely (1) blast

furnaces , for smelting an d (2) roasting furnaces , for

reduction of pyritic ores. The numbers, types and

production capacities of furnaces were determined in

order to provide the number of corresponding stacks at

each smelting facility . Cylindrical blast furnaces

alone were most commonly used during the approximate

period from 1877 to 1895, with increased pyritic

smelting then necessitating the addition of reverbatory

roasting furnaces to pretreat ores prior to smelting

after 1895.

Columns 10 and 11. Total No. of Stacks and No. of Stacks in Operation

T he total number of the given form of stack is listed. Based on historical reports of mining practices all of

the stacks never operated simultaneously, as furnaces

required repair between smelting campaigns. The number

of stacks in operation reflect s this operational

information.

Column 12. Removal Efficienc y

For smelters where dust control was practiced,

historical reports and current knowledge of smeltin g

operations were applied to estimate the percentage of

emissions removed by the dust control technology.

Columns 13 and 14. Stack Height (ft) and Stack Inner Diameter TTET

These dimensions were obtained from (1 ) insurance maps,

( 2 ) historic descriptions, (3 ) measurements from

photographs , or (4) inference; where detail s for a specifi c stack were unavailable, the stack dimensions
were inferred on the basis of comparison with similar

known or measured stacks.

Column 15. Stack Exit Temperatures (degrees C)

Precise exhaust temperature data were not foun d for

most of the stacks identified; therefore, as agreed at

t he September 27, 1991, Technical Advisory Committee

meeting, 150 C was used. Detail s regarding the

justificatio n for derivation of this value will be

provided to the EPA.

Column 16. Blast Furnace Blower Volumetric Flo w (ft-Vmin )

Historic reports listed the blower size and flo w

capacity for many of the smelters; these data were used

to infer blower capacities for similar-sized furnaces

lacking historic records of this type.

Column 17. Blast/Dus t Stack Volumetric Flo w (ft 3/min )

Stack gas volumetric flo w rates for blast furnace

stacks and associated dust stacks (if present ) are

based on the size of the air blower supplyin g air to

t he furnace (see item 17) , estimated air infiltratio n

rates, and the distribution of exhaust gas between the

dust chamber and blast furnace exhaust stack. Two

operational conditions were assumed to exist. If dust

chambers were not associated with a blast furnace, all

exhaust gases exited the blast furnace stack. If a dust chamber was used, a portion of the blast furnace

exhaust stream was diverted through the dust chamber,

while a portion of the exhaust gas continued to exit

from the blast furnace stack. Specifi c detail s on

volumetric flo w rate calculations are provided for each

of the two operational cases below.

Blast Furnace With Dust Stack

Based on current review and understanding of the

historical process description of blast furnaces

operating with dust recovery technology, about

20 percent of the volumetric flo w normally exited

through the blast furnace stack with about 80 percent

of the blower-supply flow , plus infiltration , diverted

to the dust chamber. An inflo w of 50 percent of the

blower-suppl y flo w was assumed for the volume exiting

the blast furnace stack. Therefore, the blast furnace

stack flo w rate is calculated as:

Blast Stack Q = 0.2 x (1. 5 x Blower Q).
T he dust stack associated with the blast furnace was

assumed to have an additional infiltratio n of

50 percent. Thus , the dust stack flo w rate associated

with a single blast furnace was calculated as:

Blast Dust Stack Q = 0.8 x (1. 5 x Blower Q) x 1.5.

If multipl e blast furnaces were ducted to a single dust

chamber, as was usually the case, the dust stack volume

flo w rate given above was multiplied by the number of

furnaces in operation (see item 11) . Blast Furnace Without Dust Stack

Several historic blast furnaces did not use dust and

fume recovery methods, primarily dust chambers. For

these blast furnaces , current engineering understanding

of the historic process was applied to estimate the

volumetric flo w rate. It was assumed that additional

air infiltratio n to the furnace and ducting increased

the volume of air leaving the stack 2.5 times the

blower-supplied air stream. That is, the flo w rate was

computed as:

Blast Stack Q = 2.5 x Blower Q.

Several historic blast furnaces had no dust control

technology. For these blast furnaces , current

engineering understanding of the historic process was

applied to estimate the volumetric flo w rate as 50

percent greater than the blower-supplied volumetric

flo w rate.

Column 18. Roaster Furnace Exit Velocit y (ft/min )

T he exit velocity used for dust stacks associated with

roasting furnaces represents an average obtained from

historical research reports of experimental

measurements on roasting furnaces. An average velocity

of 1,450 ft/mi n for 3.5 foot diameter stacks was

determined. Exit velocities from stacks other than

3.5 foot diameter were scaled based on the crosssectional area of the stack. It was assumed that the

volume flo w rates from roasting furnace dust stacks

were similar. Therefore , the exit velocity was

computed as:

Roaster Dust Exit Velocit y = 1450 x (3.5/D) 2;

where: D = diameter of roaster dust stack (ft) .

\
Column 19. Total Average Production Rate (tons/day )

Furnace capacities for many of the historic smelters

were available in historic literature.

Column 20. Metal s (from ) Blast/Dus t Stack Fume (Ibs/day )

T he percent concentrations of lead, cadmium, arsenic

and zinc in blast furnace fume were located in historic

reports. These values were combined with fume

production data for 35-40 tons-per-day capacity

furnace, to determine the mass of the four chemicals on

a Ibs/da y basis. The dail y load has been adjusted

using a direct proportion on the basis of blast furnace

production to estimate loads for furnaces with larger

or smaller capacities than the 35-40 tons-per-day

capacity.

Column 21. Total Metal s (from ) Blast/Dus t Stack Fume (tons )

Total metal emissions in fumes for the length of

operation (see item 8) from either a blast furnace

stack or blast furnace dust stack are calculated. Thi s

was computed as the product of the dail y average fume

emission rate (see item 20) , the length of operation in

days, and the removal efficienc y (see item 12) of the

dust and fume recovery equipment (dus t chambers). It

was assumed that both dust and fume were controlled at

approximatel y the same efficiency . Dust chambers were

used to remove dust by impaction removal mechanism,

while fume was removed by condensation.

Column 22. Metal s (from ) Blast/Dus t Stack Dust (Ibs/day )

T he weight of metals produced in dust on a dail y basis

w as estimated from historical analyses of dust for

blast furnaces with a 35-40 tons-per-day capacity.

Column 23. Total Metal s (from ) Blast/Dus t Stack Dust (tons )

Total metal emissions of dust for the length of

operation (see item 8) from either a blast furnace

stack or a blast furnace dust stack. These were

computed using the same method outlined for item 21.

Column 24 and 25. Metal s (from ) Roaster Furnace Fume and Dust TTbs/day ) an d Metal s (from ) Roaster Furnace Fume and Dust (Ibs/day )

These values were unavailable in historic literature;

however, data from the 1950s for the AV Smelters
sintering operations were available, and were used to

infer the composition of dust and fume associated with

roasting operations. Emissions were computed using

emission factors published by the EPA in AP-42

(Compilatio n of Air Pollutan t Emission Factors , Supplemen t C, September 1990 ) from sintering operations

at primary lead smelters. The emission factor provided

in AP-42 was adjusted to provide emission estimates for

the metals of concern based on the tons of ore

processed and the metals composition from the AV smelter. The adjusted emission factor used was 19.7 Ibs . metals per ton of ore processed.

PARAMETER S FOR EACH SMELTE R LOCATION (CALCULATE D VALUES )

T he data are function s of the data listed in columns 1 through 25, and represent conversions or numerical

calculations necessary to present the data into the

form needed as model input. These data columns are

discussed in the followin g paragraphs.

Columns 26 an d 27. UTM E(m ) an d UTM N(m)

U TM coordinates are listed for use as model input. Spatially , these correspond identicall y to the State Planar Coordinates listed previously, and are listed in

meters on the table.

Column 28. Stack Height (m)

Thi s column contains unit conversion values of the

values listed in English units in column 13.

Column 29. Stack Diameter (m)

Thi s area was calculated from column 14.

Column 30. Area (m^ )

Thi s area was calculated for use in other calculations.

Column 31. Stack Exit Temperature (K)

The exit temperatures listed in column 15 were

converted to Kelvin s for modeling purposes.

Column 32. Blast Furnace Stack Volumetric Flo w (m^/sec )

Thi s column contains unit conversions of the values

listed in column 17.
Column 33. Blast Furnace Stack Exit Velocities (m/sec )

T he exit velocities in this column represent the metric

value of flo w listed in column 16 divided by the stack

area in column 30 (since V = Q A).

Column 34. Blast Furnace Dust Stack Volumetric Flo w (ro^/sec )

Blast furnace dust stack flo w volumes are calculated as

described previously in item 17.

Column 35. Blast Furnace Dust Stack Exit Velocit y (m/sec )

These velocities were calculated using V = Q/A .

Column 36. Roaster Furnace Dust Stack Exit Velocit y (m/sec )

These represent conversions of values in Column 18.

Column 37. Blast Furnace Stack Emissions (g/hr )

These values were calculated from the values listed in

column 21 and 23.

Column 38. Dust Stack Emissions (g/hr )

These values represent unit conversions of the values

listed in column 21 and 23.

Column 39. Roaster Furnace Dust Stack Emissions (g/hr )

These values were calculated from values listed in column

25.

2) After Section 2.3.5, Page 2-11: Add Section

2.3.6, to be entitled "Task 5 - Buildin g Material Investigation." The new section is to read as

follows:

T he objective of Task 5 is to characterize the nature and extent

of metal contamination present in buildin g materials (e.g. ,

smelter debris, cribbing, mill buildings , etc.) in order to

determine the level of risk presented from these materials and

potential remedial response.

T he initial phase of activity for this task is to identif y and

create an inventory of the types of materials removed from

smelter sites, identif y the locations of the removed material,

and identif y the current uses of the material.
T he second phase is to create maps of the location of the removed

smelter materials, and propose samplin g locations to obtain

representative data necessary to characterize the material. The

material will be analyzed for total metals as well as mineralogy

and speciation. The data quality will be Level III at a minimum

with the laboratory/method subject to EPA concurrence.

3) Sectio n 3.0, Tabl e 3-1: The analytical method

for analysis of arsenic in soil samples is changed

to Method 200.7 CLP-M and the Reporting Limit is

changed to 10 (mg/kg) . The analytical method for

analysis of lead in soil samples is changed to Method 200.7 CLP-M and the Reporting Limit is

changed to 2.0 (mg/kg) .

IT I S S O ORDERED:

ENVIRONMENTA L PROTECTIO N AGENCY , REGION VII I

B Y : DATE : Robert L. iDu^rey, Dir^fctor XX Hazardous Wast e Manax?Q/rnenJL/pivisio n

10